The Oily Maniac (1976) on Netflix

A father, his daughter, and a friend of the family, Li Hsiu-hsien, own a coconut-oil company. They get in trouble when criminals want to take over their business. The father is thrown in prison. The daughter and the cripple, Li Hsiu-hsien, are left behind. When the daughter fails to return the love of Li, he turns to a magic spell to become strong. The spell transforms him into an oily monster/superhero that kills criminals. Li, while working in a law firm, stumbles upon a plot from his boss to steal the coconut-oil company. After the criminals kill his love, he goes on a killing spree to have his revenge. As the powerful oily maniac, he is impossible to kill, and is able to transform himself into a pool of oil to hunt down the killers.